Truck.



W. J. ADAM.

TRUCK.

7 APPLICATION FILED NOV. 27, 1311. 1,083,422. fiPaflqehted Jan. 6, 1914 a; 1 21' 21 Wzawca, ,Zizwizfir- 7M4 MW 24 2a m am ;i w

UNITED sra'rns r enema WILLIAM. J. ADAM, OF NORWOUD,

MASSAC'HUSIETILS; Assxenon, :s'r' Mnsnn assionmnn'rs re-ermrrou PRESS, or ivonwoonnAs's-iicnusnrrs; A conservation or nessncnusnr'rs.

Specification of Letters Patent.

TRUCK.

Ap ilication fi-leilNovember 27, 1911. Serial No. 682,531. I

To all whom it may concern:

Be it known that I, Vi HLLIA-M J. ADAM, a citizen of the United States, residing at Norwood, in the county of Norfolk and -State of Massachusetts, have invented certain new and useful Improvements in Trucks; and I do hereby declare the follow- I ing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains tomake and use the same.

The'pre sent invention relates to trucks, and more particularly to trucks which are provided with mechanism for elevating the table of the truck to facilitate the loading and unloading of material carried thereon.

The object of the present invention is to provide a truck of this character which will support a heavy load, and which may be readily manipulated by the operator to raise the load through a considerable vertical distance.

With this end in view, the various features of the invention consist in certainfor conveying paper or other .material or articles to different parts of a printing or iii manufacturing establishment. In conveying paper, for instance, the paper is carried upon a board which is supported upon the table of the truck with its ends projecting over the sides of the truck, and in order to re ove the load the table is elevated, allowing the projecting ends of the board to pass over a pair ofsupporting members between which the truck is moved. After the platform has been positioned above the supporting members. the table is lowered and the truck may then be removed without disturbing the board which is retained in position by the supporting members. The truck s loaded in a likemanner by'first positioni of arms ing it beneath the board and then. elevating the table of the truck to lift the board from the supporting members.

The truck is mounted upon four wheels indicated at 1, and is provided withv a front axle 2 and a rear axle 8 rigidly connected together by a pair of longitudinal braces 5. The truck is guided by turning the front wheels, which are pivoted to opposite ends of the axle 2 by steering knuckles 6. 'A pair 7 extend forward from the steering knuckles 6 and the arms are connected to a tongue 9 by links 8. The tongue is fastened Patented Jan. 6, 1914.

to the front axle 2 by a pivot bolt 10 audio provided with a handle (not shown) for v controlling the movements of the truck.

The above described portion of the truck forms a rigid support upon which the table.

rests, andmay be conveniently referred to hereinafter as the chassisof the truck. The truck is provided with a skeleton table or bed which is formed by a plurality of angle irons 11 rigidly connected together at their opposite ends. In-order'to: secure the table against horizontal movement either longitudinally or sidewise, but to allow ,a free vertical movement, the two front corners of thetable have recessed bosses 12 de pending therefrom which slidingly engage with vertical studs 13 mounted upon oppo site ends of the front axle. The rear cor-- ners of thetable have studs 15 depending therefrom which engage with upstanding stop members 16 mounted upon the rear axle to limit the downward movement of the table. In Fig. 2 the table is shown in its lowermost position with the stop members in contact supporting the rear end of the table.

It is desirable that the elevating mechanism be capable of elevating a comparatively heavy load with the application of a small pressure upon the operating lever, and that the range of vertical movementthrough which this load is lifted should be as great as possible. To this end the"elevating mechanism consists of four cam segments indicated at 20, which arepivotally connected to the four corners of the chassis alt-'21., and each of which cooperates with a wedge shaped cam 22 formed upon the under side .of the table. The cam segments 20 are oscillated relative to the cams 22 to raise or.

lower the table, and in order to'fecilitate the operation of the cams a roll 25 is inserted between each pair of cams and 22. The roll 13' retalned 1n posit-ion between the two camsby a pair of upstanding projections 26 formed upon the cam 20 and a correspond mg pair of projections 27- formed upon the cam 22. In order to move the cam segments 20 in unison, each pair of front and rear s'egmentsare rigidly connected together by a link '30. The operating lever for moving the cam segments is indicated at 32, and con sists of a bail-shaped handle pivoted to the chassis and connected to each of the front segments by a link 33. lVith this construction and arrangement of parts, upon depressing the operating lever 3:2 a powerful pressureis exerted to lift the table, raising the same evenly and uniformly"with a mini-.

mum of friction between the operating parts.

The elevating device is actuated by a toggle which consists of the operating lever pivoted to the chassis'and a link connecting the leverand elevating device adjacent the fulcrum of the lever. As the lever is depressed to straighten the toggle the fulcrum of the lever is shifted to increase the distance between the fulcrum and the link con-I nection and thus increase the resultant movement imparted to the elevating cams. In

the simplest and most, eliicient form of the invention whichhas yet been devised the lever is pivoted slidingly to the chassis, and a cam serves to shift the fulcrum. of the lever and increase the distance between the fulcrum and .the link as the lever is de-.

pressed. The lower ends of-the lever 32 are slotted, as indicated clearly in Fig. 2, and a projecting stud 35 engages with each slot.

4 cent tothepivotal connection of the link 33 This pin-andslot connection is located adjawi'tl'1'. tl1e lever and enables the distance between the fulcrum of the lever and the link to be varied. In" order to shift the fulcrum of the lever 32 as the lever is de *e'ssed a pair of cam plates 86 are secuaed to the chassis and engage with cot) crating cam rolls 37 journaled uponthe operating lever in axial alinement with the pivotalconnections of the link The table is locked in its elevated position by recesses 38 WlllCll are formed: in the front sides of the cam plates 36 and engage with the cam roll 37 when the operating lever 32 is depressed.

The operation of the elevating mechanism isas; follows: When it is desired to elevate the table in order to cithcrload or unload the truck, the operating lever 32 is depressed. The initial positionof the operating lever is that shown in Fig. 2, and in this position the fulcrum. of the lever is located in close proximity to the connection of the links 33 and a long leverage is obtained, thus exerting a powerful pressure to raise the table with the application of a comparatlvely Losaaae small force upon the operating lever, The depression of the-lever straightens the toggle consisting. of'the' lever 32 and the links 33, and as the toggle is straightened, the same pressure is exerted-to raise the table with the application of acorresp'ondinglydiminished force upon the operating lever. To. utilizethis feature the cam plates 36 shift the fulcrum of the operating lever to shorten the leverage as the lever is depressed, thus exerting a constant pressure to raise the table with the application of a substantially constant force upon the operating lever through the entire range of movement of the lever, and. the operator is enabled to obtain the maximum extent of movement of the table with 'aiminimum throw of the operating lever.

While it is preferred to employ the spepartscific construction {and arrangement of shown and described, it will be understood that this construction and arrangement is not essential except so far as specified in the claims, and may be changed or modified without departing from the broader features of the invention.

Having thus described the invention, what is claimed is 4 v 1. A truck, having, in combination, a chassis, a table supported thereon, an elevating device, a lever pivoted to the chassis, a link connecting the lever and elevating device and forming a toggle with the lever, and means for increasi the distance between the link connection'and the fulcrum of they lever to shorten the leverage as the toggle is straightened, substantially as described.

2. A truck, having, in combination, a chassis, a table supported thereon, an elevating device, a lever-pivoted to the chassis, a' .link connecting the lever and elevating device and forming a toggle with the lever,

and a cam operatively connected [to the lever and arranged to increase the distance between the link connection and the fulcrum of the lever to shorten the leverage as the lever is depressed, substantially as described. 1

3. A truck, having, in combination, a

chassis, a tablesupported thereon, an elevating device, an operating lever having a pin-and-slot connection with the chassis, a

link connecting the lever and elevating de-;

chassis, a table supportedthereon, an elevatin device, an operating'leveri pivoted to the c assis, connections/ between the lever and elevating device, and a cam for shifting the lever asit is depressed having a recess arranged to retain the lever'in its'depressed positionand hold the table elevated, substantially as described;

6.'A' truck having,. in combination, a

chassis, a table supported thereon 'for vertical movement, a wedge-shaped cam secured to theunder side of the table, a cam segment pivoted to the chassis and cooperating with the wedge-shaped cam, and a roll interposed 7 between thefaces of the two cams, thecams 9 having projections-formed thereon to retain the. roll ini ts operative position, substantially as described.

\ 7. A truck having, in combination, a

chassis, a table supported thereon, an ele:

5 vating device, a stud secured to the chassis,

a lever having'a slotted lower end engaging witli 'the stud, a'link connecting the lever andelevating device, and acamfor shiiting the lever T es it is' depressed to increasethe distance. between the link connection and the fulcrum of the lever,.substantially as described, I I 8. A truck, having, in ,combmatlon, a chassis, a cam mounted on the chassis, a vertie'a-llymovable table, a cam mounted on the table and adapted to cooperate with the'cam on the, chassis, a' freely traveling roll between the working surfaces of the two cams,

means for guiding the table in a verticalline, and mechanism under the control of the operator for moving one of the cams to raise or lower the table as desired.

9. truck, having, in "combination, a chass1s,'cam segments pivoted on the chassis,

a vertically movable table provided on its under side with bearing surfaces coiiper- 'atmg with the cam segments, a freely traveling roll between each cam segment and the opposed bearing surfa ce, vertical guides for the table, and an'operat'ing lever pivoted 0n the chassis and connected with the cam segments.

10. A truck, having, in combination, a chassis, a vertically movable table, vertical guides for the table, wedge shaped cams se cured to theunder side of the table, cooperating cam segments mounted on the chassis, a freelytraveling roll between each cam segment and the 'coiiperating wedge shaped cam, and an operating lever connected with the cam segments. Y

11. A truck, having, in combination, a chassis, "avertically movable table, vertical "guides for the table, wedge shapedcams secured to the underside of the table, cooperating cam segments pivoted to the chassis, a freelytraveling roll 'betweenleach cam seg ment and the cooperating wedge shaped cam', an operating lever pivoted on thechassis, and links connectin the cam segments with each other and with the lever.

' ILLIAM J. ADAM.

Witnesses:

FRED R. ELLIS,

MAUDE M. MILLER.

Copies '0! this patent may be obtained for five cents each, by addressing the f Commissioner. of Iatents,

' Y Washington, D. G. 

